Stable aqueous solution of ascorbic acid



Patented July 22, 1941 I UNITED STATES, PATENT OFFICE STABLE AQUEOUSSOLUTION OF 'ASCORBIO ACID 1 Carl Lu'dwig Lautcns'chlager and FritzLindner,

Frankiort-on-the-Main, Germany, assignors to I Winthrop ChemicalCompany, Inc., New York, N. Y., a corporation of New York No Drawing.Application January 23, 1936, SerialNo. 60,544. In Germany January 26,

' 6 Claims.

The present invention relates to stable aqueous solutions of ascorbicacids, more particularly to solutions of levo-ascorbic acid.known asvitamin C, said solutions being capable of being injected,

and to a process of preparing them.

As is known the ascorbic acids, especially the of 3.5 cc. of N-causticsoda solution. The solution is .made up to 100 cc. and charged intoampoules in an atmosphere of carbonic acid; the ampoules are sealed inthe carbonic acid current and sterilized for 10 minutes in flowingsteam.

levo-ascorbic acid itself, are frequently applied in medicine in theform of preparations to be administered per as but there is no processfor 'the preparation of stable aqueous solutions ofthe ascorbic acidscapabl of being injected and used for the parenteral therapy. This isdue and is made up to 100 cc. The solution is then X to the iact"thatthe compounds named cannot be iniected' at all or only with diflicultyon account oi their acid properties and that hitherto attempts had notbeen made to obtain solutions of the ascorbic acid salts becausestatements made in literature show that the acid soon decomposes in thealkaline range. m

Now we have found that supplies of stable aqueous solutions of theascorbic acids and especially of the levo-ascorbic acid can be obtainedby mixing solutions of the levo-ascorbicacid with basic substances whichreduce the acid degree of the solution and filling the solutions thusobtained with the aid of inertgases, while excluding oxygen, intoampoiles or other containers capable of being hermetically sealed. As

basic agents there may, for instance, be used sodium carbonate, causticsoda solution, calcium hydroxide, magnesium hydroxide, ammonia,furthermore triethanolamine, amino-ethanol or any other organic bases;these agents are used in such an amount'that the acid dissolved ispartly or completely neutralized. As inert gases there may be appliednitrogen, hydrogen, carbonic acid and the like. The solutions may bekept sterile by sterilizing additions or 'by the sterilization oftheampoules which are free from additions and they may be injectedwithout causing irr'l tation.

The solutions prepared according to this process are stable for, a verylong time if they are stored with exclusion of oxygen; theascorbic acidcould, for instance,-be reobtained in an unaltered purity from a 9months old solution.

The following examples serve to illustrate the invention, but they arenot intended to limit it thereto:

1. 2.5 grams of levo-ascorbic acid are dissolved in water; the whole isadjusted to a hydrogen ion concentration of about 4.0 by the addition22.5 grams of levo-ascorbic acid are dissolved in water; the solution isadjusted to a hydrogen ion concentration of about 6.5 by the addition of16 cc.- of N-caustic soda solution or the correspondingamount of sodiumcarbonate solution 1. An anti-scorbutic solution adaptable forhypodermical, administration containing an ethanol amine salt 151'ascorbic acid.

2. An anti-scorbutic solution adaptable for hypodermical administrationcontaining theethanol amine salt .of ascorbic acid. r

' 3;. An anti-scorbutic solution adaptable for hypodermicaladministration containing the triethanol amine salt of ascorbic acid.

4. An aqueous solution containing ascorbic acid and an ethanol amine inan amount not suflicient for complete neutralization of the acid, saidsolution being non-stable to oxygen and stable to inert gases and havinga pH value between about 4 and 6.5. a

5. An aqueous solution containing ascorbic acid and ethanol amine in anamount not sumcient for complete neutralization ofthe acid, saidsolution being non-stable to oxygen and" stable to inert gases andhaving a pH value between about 4 and 6.5. y

6. An aqueous solution containing ascorbic acid and triethanol amine inan. amount not suflicient for complete neutralization of the acid, saidsolution being non -stable to oxygen and stable to inertgases and havingapH value be-' tween about 6.5.

CARL LUDWIG LAVUTENSCHLA Ea.

